Electric servo for vehicle brakes



Sept. 28 1926. 1,501,432

B. G. PARSONS ELECTRIC SERVO FOR VEHICLE BRAKES Filed Feb. 24, 1925 Mum 'INVENTOR BE G. PARSONS ATTORNEY Patented Sept. 28, 1926.

UNITED STATES PATENT- OFFICE.

and is omobile This invention relates to bra illustrated as embodied in an au chassis- An object of the invention is to lost provide a novel wer device, shown oper- 6 sted by an electric motor, controlled by the brake pedal or other operating member, and operatlveto set the brakes. I consider it lnghltylrl desirable to arr the device so that e driver may apply the brakes direct- 1y by the same 0 ting member, in case power is not avai able for any reason, or is msuliicient. One erran meut includes a connection for applying e brakes by power, and which is so operative to control the I power, as by opening a switch for the motor circuit t9 prevent waste of current by running the motor continuously while the rakes are on. In the arran ment shown in the drawings, depremion o a pedal closes the motor circuit and at the same time throws in a clutch geared to the motor, the clutch operating t rough a novel linkage to apply the brakes, and application of the brakes m a dedepending on the position of the pedal on serving to o n the motor circuit again. Preferably the c utch is o ated by the motor through an irreversib e earl so that the brakes, when once applle are old until the ressure on the a is released. to The above and 0 er ob ects and features of the invention, ineludin various novel combinations of parts and esirable eular constructions, will be apparent om the following description of one illustrative em- 86 bodiment shown in the accompanymg drawin in which:

i igure 1 is a diafipammatic top glen view of an automobile c assis having rakes on its four wheels; and

re 2 is a side elevation of the pedal and e connections from the pedal controllin the motor and clutch; and

l igure 3 is a sectional view of the gearing between the motor and clutch.

In the arran ment selected for illustration the chassis includes road wheels 10 having brakes operated by a 11 connected to a rock shaft 12, the shaft having an arm 14 connected to a link 16, which is thus an operative to set all the brakes.

The brakes are controlled by a pedal 18 having a pro ection flltlhwhiish, aftegga 8:101:15 me on, eng e unger 0 an electncsmtch M llirunt on one arm of e bellcrank lever 26, thus closing the circuit 28 of an electric motor 30. Motor 80 oper ates throu hwonn 82toturn one member of a friction c utch, the other member 86 of which carries an arm 38 voted to a link 40. Depression of ped 18 also operates throuFh a link 4-2 to rock an arm 44 to force the we friction clutch members 34 and 36 together, so that member 36 is turned by the motor to apply force to lmk 40. Linkflf) is formed with a slot 48 embracmg a pm 48 carried by a lever pivoted at 52, so that when the clutch is opera okelzy repressingl the pedal, the lever is re while If e current is not on or if the motor cannot so ply sullieient iorce, lever 50 can be rocke manually on account of the lost motion allowed b slot 46. Lever 50 is connected by a link 5 to the bellcrank lever 26, and also to the link 16 which a plies the brakes. When 31:11 pedal is release a spring r ii h m ped 1' depressed nopers on,w en a a 18 the clutch is closed and the switch 24 is operated to close the motor circuit; the motor then 0 rates through link 40 to rock lever 50 an applyeethe brakes. As soon as the brakes have n applied in a degree which is a function of the lever 50 operates throu the bellcrsnk lever away from the pedal and o n the switch afsin. Any slippage of the c ntch, or an urther do resszon of the pedal, again uses the swxte to apply more power to the brake, while when the pedal Is released the spring 56 returns the parts to normal positions.- 1

While one illustrative embodiment has been described in detail, it is not my intention to limit the scope of the invention to that lparticular embodiment, or otherwise thin lay the terms of the appended claims.

1. A vehicle havingI in combination, braking means, a centre ling member, powerposition of the pedal, gh link 5* to rock operated means, and connections controlled b said member for applying the brakes by t e power of said means to an extent determined by the 'tion of said member and then cuttin o the ower and holding the brakes, sai member g arranged to permit the appllication of manual power directly to so: connections 2. A vehicle having, in combination, bralo ing means, a controlling member, an electric motor, a circuit for the motor, and connections from said member for applying the braking means to an extent determined by the position of said member-by the power of the motor and then automatically opening the motor circuit, said member being arranged to permit the application of manual the o eratin power directly to said connections.

8. Avehicle havi in combination, electrically-operated hr as a circuit therefor iflBIlIdl-Ilf a switch, an o rating member, a carriea o1;x5 the swgletghfi t g switchtbeing arran to en' t e opera mg member for cl the izircuit and means mechanically operated by application of the brakes for movi the carrier away from mem r to open the circuit.

4. vehic e having, in combination, brakes, aclutch, means operated by the clutch for applying the brakes, electric means for driving he clutch, a circuit for said means, an operating member connections from the operating member {or throwing in the clutch and closing the circuit, and means operated by the clutch for operating said connections to open the circuit without throwing out the clutch.

5. A vehicle having, in combination, braking means, an electric motor arranged to operate said means, a switch controllin the motor circuit, a lever for closing the switch, and means mechanically operated by the motor for moving the switch away from the lever to o n it 6. A ve icle having, in combination, operating connections, an electric motor arranged to operate said connections, a motor circuit including a switch, an operating pedal, and a lever on 'ng the switch in the path of the pedal an arranged to operate the connections manually in case the power of the motor is insuflicient.

7. A vehicle having, in combination, brak ing means, an electric motor arranged to operate said means, a switch controlling the motor circuit, a manually-operated member for closing the switch, and means operated by the motor for moving the switch m a direction to open it again when the motor has turned through an angle determined by the extent of movement of said member, together with connections from the same member for applying the brakes manually.

A vehicle having, in combination. brakingmeans, a controlling lever, on adjacent lever arranged to operate the braking means, a power device, and means for controlling said device carried by the adjacent lever in the path of the controllin lever and rocking the adjacent lever to app y the brakes when power is not available, said means operating to cause the power device to become operntive to ap ly the brakin means when ongaged by t 1e controlling ever, and the aplication of the brakes rocking said adjacent ever to move the controlling means away from the controlling lever to cut out the power device. 9. A vehicle havin ,in combination brakmg means, a centre lever, an adjacent lever, a war device arranged to operate the braking means, and means for controlling said device carried by the adjacent lever ll] the path of the controlling lever said means operating to cause the power evice to become operative to appl the braking means when enaaged t controlling lever, and the app cation of the brakes rocking said adjacent lever to move the controlling means away from the controlling lever to cut out the power device.

10. Operating mechanism comprising, in combination, an electric motor an operating pint moved thereby, a controlling switch for the motor circuit, a controlling lever movable to engage and close the switch, and means operated by movement of said eratin part by the motor to move the switch bodi y away from the controlling lever to open the motor circuit.

11. Operating mechanism comprising, in combination, an electric motor, reduction gearing driven by the motor, an operating part moved by the gearing, a controlling switch for the motor circa: a controlling lever movable to eng and one the switch and means operated y movement of said operating art by the motor to move the switch b ly away from the controlling lever to open the motor circuit.

12. Operating mechanism comprising, in combination, on electric motor, a movable operating part, gearing driven by the motor and moving sand art, the gearing including a clutch, a switc controlling the motor, a controlling lever arranged to en age and close the switch and to throw in t e clutch, and means operated by movement of the operating part to shift the switch with respect to the controlling lever to open the switch again.

13. Operating mechanism comprising, in rmnliination, nnclcctric motor, a movable operating! part. gearing driven by the motor and moving said port, the gearing includin a clutch, 0. switch controlling the motor, a controlling;' lever arranged to engage and close the switch and to throw in the clutch, and means operated by movement of the operating part to shift the switch with respect to the controlling lever to open the switch again Without throwing out the clutch, reverse movement of the controlling lever throwing out the clutch without effecting the switch.

14. Brake-operating mechanism comprising, in combination, a brake-applying lever (50) having a brake connection (16) at one end and fulcrumed between its ends, a menually-operated lever (18) having lost-motion 10 motion connection to the opposite end of the lever.

In testimony whereof I have hereunto subll scribed my name:

BEN G. PARSONS.

ally-operated lever (18) having IOSii BEGtiOH 16 connection to said end of the lever, and power-operated means (40) having Ecstmotion connection to the opposite end of the lever.

In testimony whereof I have hereunto snbll scribed my name BEN G. PAESGNSQ Qeri ificate of Correct-ion I 82 i upon the application of Ben G.

t is hereby certified that Letters Patent No.

i p. W-i f q i as 1 (.7 arsons o i om-li enc, loomin o 1m impim cincni lt' ieciric SETVOS for Vehicle BlfiliT-BS," Was crroncousl 1,601 ,4] granted September issued 10 the inventor; said Parsons, Whereas said Letters Patent should have been issued to Tim Rende'xfh'oke (lompmvy, as assignee of the amine as shown by the records of assignments Patent should be read with this correction therein the l'fitlilid o'f ilie case in the Patent Office.

interest in said iiiwni'ion 1n oiiice: and. that the sand Leilcrs inc? ike some may con form in figncii and sealed this 16H) day of November 1 1. I 18:26:

M: J. MOORE Acting C am/missions? of Pacmis.

Certificate of Correction.

It is l'lereb I certified that Imt-tcrs Patent No. 1,601,419. granted September Q8, 1926, upon tw up Iicatinn of Ben G. Parsons. of Smut-h Bend, huiiana, for: an impnwemcnt in Electric Servos for Vehicle Brakes, was erroneously issued in [he invnntor, stud Parsons, whereas said Letters Patent should have been issm-d to Tim li'muiiw Brake Omnpamy, as assignee of the entire interest in said lnwnfiun as shown by the records of assignments in this office; and that (he said Lenora Pate-m. should be read with this correction therein ihnt. the same may conform to the rrzwrd (if the case in the Patent Ofiioe.

Signed and sealed this 16th day of November, A. D. 1926.

- M. J. MOORE, Acting Commissioner of Pawm'b, 

